Frost Dates for 37854 — Rockwood, Tennessee

Half of springs at Rockwood 2, TN see their last 32°F night by April 8; only one in ten is past it by March 22, and one in ten still has one after April 26. Planting tender crops after April 16 leaves a 30% risk of a frost on them, after April 20 20%, and after April 26 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 67% of the 144 Tennessee stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 31 in half of years, as early as October 18 one year in ten, and holds off past November 12 one year in ten. A hard freeze of 28°F follows 9 days later, around November 9; in spring the one-in-ten date for 28°F is April 14, 12 days before the 32°F one. The freeze-free season lasts 203 days in a typical year, shorter than at 52% of the 144 Tennessee stations; it reaches 225 days one year in ten and falls short of 180 one year in ten. On average 93 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 14 days longer, to about April 22, and return around October 22. Severe cold of 16°F or below comes in 96% of winters, usually between December 29 and February 9.

July is the warmest month at Rockwood 2, TN, averaging 88°F by day and 66°F at night; January is the coldest at 47°F and 28°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 72% of years.

Warmth for growing adds up to 4,116 growing degree days a year (base 50°F), fewer than at 76% of the 144 Tennessee stations. 37% of them (1,524) have built up by the end of June, and July adds the most, 832. Precipitation totals 60.5 inches a year, most in July (6.0") and least in October (3.5"); May to September bring 40% of it.

The nearest other station, Kingston, TN, 10 miles east of Rockwood, has a last frost 5 days earlier (April 3), a first frost 4 days later (November 4), a season 12 days longer.

The first measurable snow (0.1 inch or more) in Rockwood usually arrives around January 17, and the last of the season around February 4. Those are the middle dates across the winters of 1991–2020 at Decatur 7NE, TN, 15.5 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 63 days after the last snow.

ZIP 37854 is 2 miles from Rockwood 2, TN, which stands at 767 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 37854 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°C) over 1991–2020; a zone describes winter lows, not frost dates.